﻿    <p>
      The element type
      (<em>IfcSpatialStructureElementType</em>) defines a list of
      commonly shared property set definitions of a spatial
      structure element and an optional set of product
      representations. It is used to define an element
      specification (i.e. the specific element information, that
      is common to all occurrences of that element type).
    </p>
    <blockquote class="note">
      <p>NOTE&nbsp; The product representations are defined as
        representation maps (at the level of the supertype
        <em>IfcTypeProduct</em>, which gets assigned by an element
        occurrence instance through the
        <em>IfcShapeRepresentation.Item[1]</em> being an
        <em>IfcMappedItem</em>.
    </blockquote>
    <p>
      A spatial structure element type is used to define the
      common properties of a certain type of a spatial structure
      element that may be applied to many instances of that type
      to assign a specific style. Spatial structure element types
      (the instantiable subtypes) may be exchanged without
      being already assigned to occurrences.
    </p>
    <blockquote class="note">
        NOTE&nbsp; The spatial structure element types are
        often used to represent catalogues of predefined spatial
        types for shared attributes, less so for sharing a common
        representation map.
      </p>
    </blockquote>
    <p>
      The occurrences of subtypes of the
      abstract <em>IfcSpatialStructureElementType</em> are
      represented by instances of subtypes of
      <em>IfcSpatialStructureElement</em>.
    </p>
    <blockquote class="history">
      HISTORY&nbsp; New entity in IFC2x3.
    </blockquote>